Origin and synthesis of α-macrofetoprotein in Zajdela ascites hepatoma-bearing rats

Abstract

Both host liver and hepatoma cells synthesize α-macrofetoprotein and albumin in rats transplanted with Zajdela ascites hepatoma cells. Failure to detect α-fetoprotein in either the serum or ascitic fluid of these tumor-bearing animals suggests that these hepatoma cells have lost their capacity to produce this fetoprotein without affecting their malignant properties. Evidence that α-macrofetoprotein did not appear in the ascitic fluid before it became bloody, and was not secreted from Zajdela ascites hepatoma cells incubated in vitro suggests that (1) most of the α-macrofetoprotein found in the serum and ascitic fluid of rats with this hepatoma originates from the host liver rather than from the tumor cells and (2) secretory mechanisms for serum proteins are defective in Zajdela ascites hepatoma cells.